Cleaning compositions

ABSTRACT

Electrical machinery whose insulation is contaminated by moisture, salts, carbonaceous matter, and the like is cleaned by spraying with a solution of a water-insoluble, cationic surfactant with a hydroxy-aromatic acid or ester of such acid in a hydrocarbon solvent. The full resistance of the insulation is restored, and the residual protective film formed after volatilization of the solvent may serve as a primer for subsequently applied varnish.

O United States Patent [151 3,673,097

De Vroome June 27, 1972 [54] CLEANING COMPOSITIONS [56] References Cited [72] inventor: Harry Clarence De Vroome, London, En- UNITED STATES PATENTS gland 2,704,733 3/1955 Pearsall ..134/40 x [73] Assignee: Ayrodev Processes Limited, Poplar, En- 2,758,948 8/1956 Simon et al. ....l34/40 X gland 2,866,726 12/1958 Vance ..134/40 X 3,085,918 4 i963 Sherliker et al ..252 153 X [22] Filed: Feb. 24, 1969 l l [21] APPLNO; 801,778 Primary Examiner-Mayer Weinblatt Attorney-Kelman and Berman [30] Foreign Application Priority Data [57] ABSTRACT Aug. 14, I968 Great Britain ..38,797/68 Electrical machinery whose insulation is contaminated by moisture, salts, carbonaceous matter, and the like is cleaned by spraying with a solution of a water-insoluble, cationic sur- [52] US. Cl ..252/153, 252/118, 252/546, factam with a hydmxy aromatic acid or ester of Such acid in 3 252/527 134/40 hydrocarbon solvent. The full resistance of the insulation is [51] Int. Cl. ..Clld 1/38,Cl 1d 3/26 restored, and the residual protective film formed after [58] Field ofSearch ..252/152, 153, 1 l8; 134/40 volatilization of the Solvent may Serve as a primer for sequently' applied varnish.

5 Claims, No Drawings CLEANING COMPOSITIONS The present invention relates to cleaning compositions capable of both cleansing insulated surfaces which have become defective and contaminated with carbonaceous matter, salts, water and other contaminants, and providing a priming coat for subsequent re-insulation. Such compositions are intended to be employed for instance in the cleansing of rotating electrical machinery in which electrical resistance has been impaired by exposure to adverse conditions, including such machinery in marine service, the compositions also serving to prime the machinery for the re-application of insulating varnish or other coating media.

When electrical machinery has been adversely affected by exposure to conditions causing deterioration of the insulation of such items as generator coils, it has been the practice to remove dirt and accumulated carbon deposits by means of cleansing, solvents. Frequently such cleansers incorporate materials of an oily nature to assist preferential wetting of moist surfaces by the cleanser, and to afford a degree of protection of exposed metallic surfaces against atmospheric corrosion, re-adsorbtion of moisture or other adverse influences. The oil deposits remaining from such cleansers frequently interfere with the drying and curing characteristics of subsequently applied insulating varnishes.

It is known that most solid surfaces possess electronegative charges which are strongly attractive to the electropositive groups in cationic surfactants. Although such cationic surfactants are not ionized in non-polar solvents, these attractive forces are nevertheless operative under these conditions, for example in hydrocarbon solvents. This phenomenon is exploited in many applications, particularly in the dispersion of pigment aggregates and preferential wetting of surfaces by non-polar solvents under moist conditions. Furthermore, it is known that cationic surfactants, particularly those which are substantially insoluble in water but highly soluble in non-polar solvents, are more strongly adherent to solid surfaces under moist conditions. The non-polar moieties of the adherent cationic surfactants being directed away from the substrate surface for a moisture-repellent, non-polar covering over the substrate surface.

According to one aspect of this invention, we provide a composition containing a cationic surfactant comprising an organic acid salt of a primary, secondary, tertiary or quatemary amine containing a hydrocarbon moiety of not less than 12 carbon atoms; a hydroxy aromatic acid or ester thereof; and at least one organic solvent. The proportions of the said surfactant to the said hydroxy aromatic acid or ester thereof may vary over a wide range, for instance from percent by weight to 90 percent by weight of the said surfactant to the said hydroxy aromatic acid or ester thereof. Expediently, the proportion of the said surfactant to the said hydroxy aromatic acid or ester thereof may be from 35 percent by weight to 65 percent by weight. It is preferred that the cationic moiety of the surfactant should contain at least two like or unlike amino groups.

According to another aspect of this invention, we provide a method for cleaning a contaminated surface comprising applying to the said surface the composition of this invention and allowing the solvent(s) to volatilize, thereby cleaning the surface and forming a protective film thereon. The preferred method of application is by spraying. An insulating varnish or other coating may then be applied, e.g. by spraying, to the said protective film.

According to a further aspect of this invention, we provide a method for cleaning a contaminated surface comprising applying to the said surface components which will react in the presence of organic solvent in situ to form a cationic surfactant comprising an organic acid salt of a primary, secondary, tertiary or quaternary amine containing a hydrocarbon moiety of not less than 12 carbon atoms; a hydroxy aromatic acid or ester thereof; and at least one organic solvent; and allowing the solvent(s) to volatilize thereby cleaning the surface and I forming a protective film thereon. The said surfactant-forming components may be, for instance, the inorganic salt of the corresponding amino compound and an organic acid or a salt thereof. Here also, the preferred method of application is by spraying. As above, an insulating varnish or other coating may then be applied, e.g. by spraying, to the said protective film.

According to a still further aspect of this invention, we provide a method for cleaning a contaminated surface comprising applying to the said surface a cationic surfactant comprising a hydroxy aromatic acid or ester salt of a primary, secondary, tertiary or quaternary amine containing a hydrocarbon moiety of not less than 12 carbon atoms, and at least one organic solvent, and allowing the solvent(s) to volatilize thereby cleaning the surface and forming a protective film thereon. As above, the preferred method of application is by spraying. Also, an insulating varnish or other coating may then be applied, e.g. by spraying, to the said protective film.

The said cationic surfactant may be derived from the following amines: Aliphatic amines of the type:

R-N and R-NY wherein R an aliphatic hydrocarbon group of C and X,Y,Z hydrogen or a C aliphatic radical.

Diamines of the type:

R.NH.(Cl-l ,.Nl-l wherein x can vary from 1 to 6 and R is as above.

Higher alkyl amines of the type:

R.NH(CH H NH) C H OH wherein x and R are as above, which are synthesized, for example by the reaction of ethanolamine sulphuric esters with fatty amine salts in the presence of strong alkalis, and alkyl polyamines formed by the reaction of C alkyl halides with triethylene tetramine. Ester linked polyamines formed by the reaction of fatty esters of ethylene chlorhydn'n with diethylene-tetramine or triethylenetetramine. 81 by Ether linked amines of the type:

R---O(CH .NH wherein R is as above, formed by reacting fatty alcohols with acrylonitrile and hydrogenating the resulting cyanoalkyl ethane.

Amide linked amines of the type:

RCONH(CH NH wherein R is as above. Aminomethyleneamides of the type:

wherein a and b are lower alkyl and/or hydroxy alkyl, and R is as above. lmidazolines of the type:

wherein R is as above, and which form complex fatty acids not true salts. Quinazolines of the type:

OCH2 R.C\

wherein R is as above, and which form complex fatty acids not true salts.

Piperazine Derivatives such as alkyl derivatives of 1,4-di-(B- hydroxyethyl) piperazine formed by the monoor di-esterification, etherification of di-(B-hydroxyethyl) piperazine with C long chain alkyl carboxylic acids or halides.

wherein R is hydrogen or C alkyl or alkoxy and R is C alkyl or alkoxy.

Guanidine Derivatives of the type:

RNH-NHNH and lower alkyl, cycloalkyl, aryl, aralkyl substituted derivatives thereof, wherein R is C alkyl. Guanamine Derivatives of the type:

and their secondary and tertiary amino derivatives, wherein R is C alkyl.

Bi-cyclic Compounds.

Bis-imidazoline compounds, formed from the reaction of dibasic carboxylic acids with higher alkyl substituted 2- hydroxyethylimidazoline.

In the above list of amines, it should be mentioned that R may include substituted alkyl (C C groups including a hydrophobic group, e.g. tertiary substituted phenol groups (e.g. a tertiary octyl phenol group), a dodecylbenzene group or an abietinyl or a dehydroabietinyl group.

The said cationic surfactant may be derived from the following quaternary amines:

l. Mono and poly quaternized, analogues of the primary, secondary and tertiary amino groups mentioned above.

Where the compounds listed involve, for example, primary and secondary amino groups in addition to the amino group containing the hydrophobic group, it is to be understood that their secondary and tertiary analogues are also included.

2. Principal Commercially Available Quaternaries. Single Quaternaries.

wherein R is the C alkyl hydrophobic group, a, B and c are mainly lower alkyl groups but can also include as single substituents: v

Aryl oxy ether groups, e.g. ArOC H,

Hydroxybutyryl groups, particularly where R is a higher alkylbenzyl radical. X, normally a halide ion, would become an organic anion by double decomposition. Cyclic Quaternaries. Alkyl pyridinium salts, e. g. cetyl pyridinium salts. And analogous substituted pyridines, tetrahydroquinolines and isoquinolines. Pyridinium derivatives of halogen amines with two quaternary N functions but with only one hydrophobic group, e.g. the reaction product of 2-chlorethyldimethyldodecylammonium chloride with pyridine. N-Alkyl Morpholines.

analogous and piperidine analogues, wherein R is C alkyl, and where a is a lower alkyl.

Analogously alkylbenzyldimethylamines may be quaternized with dihalo compounds of the type CLCl-b-CONl-lc H NH.CO.CH CI and higher alkaryl ethers may be chlormethylated then quaternized with tertiary amines, including for example, benzydimethylamine and pyridine.

Ether linked Quatemaries.

For example, by reacting epoxyethers such as 3-octyloxyl ,2- epoxypropane with tertiary amines such as pyridine.

Ester linked Quatemaries.

by quatemizing esters of triethanolamine, with for example. benzyl halides.

Amide linked Quatemaries.

Formed by quatemizing tertiary amines of the type:

with, for example, chlormethylstearamide a, b, c and d may be lower alkyl or in cyclic structures.

Zelan is of this type.

Aerosol S E is an amide linked quaternary of the type:

Organic acids from which the said cationic surfactant salts may be derived may be selected from: C Aliphatic, straight-chain saturated or ethylenically un saturated monobasic carboxylic acids, preferably C such as oleic acid, stearic acid, linoleic acid, oleostearic acid, capreic acid, dodecanoic acid.

C preferably C branched-chain saturated or ethylenically unsaturated monobasic carboxylic acids.

C Cyclo aliphatic, aromatic carboxylic acids and substituted derivatives thereof, such as: salicylic acid, abietic acid, hydrogenated abietic acid and dehydroabietic acid, benzoic acid, hexahydrobenzoic acid and substituted derivatives thereof.

Polybasic carboxylic acids (C such as adipic acid, isophthalic acid, hexane dicarboxylic acid.

The said hydroxy aromatic acids and esters thereof may include: salicylic acid, -m-hydroxybenzoic acid, -p-hydroxybenzoic acid, the dihydroxy isomers of benzoic acid, the mono-, diand tri-hydroxy isomers of the naphthoic acids, and their esters with C mono or dihydric alcohols.

Solvent Basis.

Whereas the normal commercially available aliphatic hydrocarbon solvents, such as white spirit, S.P.B.3 are satisfactory for the purpose of this invention, their performance may be improved by the introduction of, for example, aromatic solvents such as toluene or xylene, and/or terpene based solvents, such as turpentine, dipentene, and the like.

A solvent blend may be selected of appropriate volatility and solvent power as required and, according to the severity of the cleansing operation and its environment. Other known solvents such as chlorinated hydrocarbons may also be included.

EXAMPLE:

A 600 kw. D.C. armature, 3% tons in weight coupled to a commutator 1 foot 6 inches long and 2 feet 6 inches diameter, installed on a ship had become heavily encrusted with oil, salts and a carbon deposit. It was ascertained that the electrical resistance of the windings had fallen to a value of 100,000 ohms. at 87 volts.

After spraying with the following composition, which rapidly dispersed the encrusted deposit, the insulation resistance, when measured 4 hours after the commencement of application, had risen to a value of 20 megohms.

Dioleate salt of -N-stearyl-n-pro pylene-l ,3-diamine (marketed under the registered trade name "Duomeen TDO") 22 parts by wt. Methyl salicylate 15 parts by wt. White spirit 250 parts by wt. Dipentene 75 parts by wt.

dihydroxybenzoic acid, monohydroxynaphthoic acid, dihydroxynaphthoic acid, and trihydroxynaphthoic acid; and

c. a hydrocarbon solvent medium,

1. said surfactant and said acid or ester thereof being dissolved in said medium in an effective concentration,

2. the weight of the dissolved surfactant being 10 percent to percent of the weight of said acid or ester.

2. Composition according to claim 1, wherein the weight of said dissolved surfactant is 35 percent to 65 percent of the weight of said acid or ester.

3. Composition according to claim 1, wherein said surfactant has an alkyl moiety of 12 to 22 carbon atoms bound to amino or ammonium nitrogen.

4. A method for cleaning a contaminated surface comprising applying to the said surface the cleaning composition claimed in claim 1 and allowing the solvent medium to volatilize, thereby cleaning the surface and forming a protective film thereon.

5. Method according to claim 4, wherein said composition is applied to the said surface by spraying. 

2. the weight of the dissolved surfactant being 10 percent to 90 percent of the weight of said acid or ester.
 2. Composition according to claim 1, wherein the weight of said dissolved surfactant is 35 percent to 65 percent of the weight of said acid or ester.
 3. Composition according to claim 1, wherein said surfactant has an alkyl moiety of 12 to 22 carbon atoms bound to amino or ammonium nitrogen.
 4. A method for cleaning a contaminated surface comprising applying to the said surface the cleaning composition claimed in claim 1 and allowing the solvent medium to volatilize, thereby cleaning the surface and forming a protective film thereon.
 5. Method according to claim 4, wherein said composition is applied to the said surface by spraying. 